class Point {
  var rho, theta;
  Point(this.rho, this.theta);
  x() => rho * cos(this.theta);
  y() => rho * sin(this.theta);
  scale(factor) => new Point(rho * factor, theta);
  operator + (p) => new Point(x() + p.x(), y() + p.y());
  static distance(p1, p2) {
    // var
  }
}

void main() {
  var name = 'Voyager I';
  var year = 1977;
  var antennaDiameter = 3.7;
  var flybyObjects = ['Jupiter', 'Saturn', 'Uranus', 'Neptune'];
  var image = {
    'tags': ['saturn'],
    'url': '//path/to/saturn.jpg'
  };
  // print(name);
  // print(year);
  // print(antennaDiameter);
  // print(flybyObjects);
  // print(image);
  if (year >= 2001) {
    print('21st century');
  } else if (year >= 1901) {
    print('20th century');
  }

  for (var object in flybyObjects) {
    print(object);
  }
  for (int month = 1; month <= 12; month++) {
    print(month);
  }
  while(year < 2016) {
    year += 1;
  }
}